Gasoline compostion



United States Patent GASOLINE CGMPOSITION Maurice R. Barusch and EddieG. Lindstrom, Richmond,

N0 Drawing. Application April 19, 1954 Serial No. 424,244

9 Claims. (Cl. 44-66) This invention relates to an improved hydrocarbonfuel composition suitablefor operation in a spark-ignition internalcombustion engine, and particularly to a gasoline composition containinga unique addition agent which functions to reduce deposits in theinduction system of spark-ignition engines.

In certain types of automotive engine service, rough idling and enginestalling has long been a consistent problem and has required frequentcarburetor adjustments and reconditioning in order to maintainsatisfactory operation. This problem of poor idling operation has beenaccentuated and expanded with the increased traffic density inmetropolitan areas and the use of multi-throat carburetors in privateautomobiles. It has been determined that a primary factor in poor idlingoperation is an accumulation of deposits in the throttle body section ofthe car- 'buretor which causes an over-rich mixture at idle and areduction in idle speed. The accumulation of deposits in the inductionsystem of the engine and particularly in the throttle section of thecarburetor is particularly pronounced in services requiring considerableidling, such as taxicab and door-to-door delivery service. In privateautomobile operation, this problem is particularly emphasized in themetropolitan areas where heavy city traffic is encountered withappreciable stop-and-go driving.

The critical accumulation point for these deposits is adjacent to thethrottle plate, whose position controls the air-fuel ratio. As thesedeposits accumulate, the air flow at idle is restricted with no changein fuel flow and a rich mixture results causing erratic idling andengine stalling. In order to compensate for the presence of thesedeposits, the throttle must be opened slightly by increasing the idlespeed adjustment which, although allowing more air flow, automaticallysupplies more fuel. This requires a fuel correction by changing the idlemixture adjustment screw a compensating amount. The amount of idleadjustment required to maintain satisfactory idle performance is anindication of the deposit build-up. Furthermore, deposits will oftenform in the idle air passageway causing restriction which allows themanifold vacuum to draw more gasoline into the engine, again causingrich idle and engine stalling.

It has been established that the primary source of these deposits is thecontaminants in the intake air of the engine when operating at idle. Thegreatest source of these intake air contaminants is engine blowby, whichaccounts for approximately one half of the deposits. Exhaust from othervehicles, dust, and other components classed as normal air pollutantscontribute to the formation of deposits.

The hydrocarbon components of the gasoline fuel bear no direct relationto the formation of these deposits. Tests have been indicated thatunstable or aged gasolines having a high ASTM gum or high potential gumvalues produce no greater deposits than stable, low-gum gaso lines undercomparable operating conditions.

In contrast to the periodic mechanical adjustments and enginereconditioning necessary to compensate for the presence of thecarburetor and induction system deposits,

it has now been found possible to provide a fuel composition which iscapable of preventing an accumulation or build-up of these deposits andwill also function to reduce the existing deposits. Thus, by operating asparloignition engine with a fuel composition compounded in accordancewith the present invention, it is possible to materially improve theidling operation of the engine and sustain this improved operation evenunder adverse conditions of intake air pollution.

It has been discovered that the incorporation in a hydrocarbon basefuel, boiling within the gasoline boiling range, of a small amount of anoil-soluble aliphatic-substituted amino alkylene amide of a higher fattyacid containing a terminal hydroxyl group in the aliphatic substituentwill provide a fuel composition which will elfectively inhibit thebuild-up of deposits in the carburetor of an engine operated thereon. Inaddition, a gasoline composition containing this improving agent willsubstantially reduce and prevent the formation of deposits throughoutthe area of the air-fuel induction system of the engine.

A particular class of compounds which function as the above uniqueimproving agents may be represented by the following general formula:

in which R is an acyclic hydrocarbon radical containing 11 to 17carbon'atoms, A in an alkylene radical and preferably an alkyleneradical containing 2 to 4 car bon atoms and, in the two occurrences ofR, one is hydrogen and the other is an aliphatic radical containing 2 to4 carbon atoms and containing a terminal bydroxyl group. It will benoted that the alternate positions of the aliphatic radical R in FormulaI are representative of the isomeric forms of the compound, both ofwhich are normally present to a greater or lesser extent, depending uponthe reaction employed in the preparation of these compounds. Theseisomeric forms may be conveniently referred to as a linear amino amidewith reference to the form:

with respect to the following form:

E III wherein the symbols R and A follow the definitions given forformula I and R is an aliphatic radical containing from 2 to 4 carbonatoms and a terminal hydroxyl group.

The improving agents of the invention may be prepared in accordance withconventional reactions involving the formation of amides. Thus, thesecompounds may be prepared by condensation of a higher fatty acid, a saltor an ester thereof with N-aliphatic-substituted alkylene diamines underconditions of reaction such as to control the condensation to theelimination of one mole of water. The higher fatty acid component of thereaction may be an acid such as lauric, myristic, palmitic, stearic,

linoleic or oleic acid, while the diamine reactant is prefproying.agents of the invention in the form of a concentrate to facilitatehandling problems and permit a simple blending operation in theincorporation of the additive in the fuel. In the preparation of theconcentrate, the improving agent is dissolved in a hydrocarbon solvent,andparticularly an aromatic solvent, in a concentration range of atleast percent by weight and up to about 70 percent by weight.

The improving agents of the invention, by'reason of their uniqueeffectiveness, are incorporated in the hydrocarbon base fuelinrelatively small amounts and preferably within the range of about0.0003 to 0.1 percent by weight. Although larger concentrations may beemployed, their effectiveness insofar as the reduction of carburetordeposit build-up does not materially improve withadditionalconcentration of the additive.

While the foregoing description of the improving agents of the inventionare directed to the free amino amide compounds, certain modifications incomposition of the agents may be employed to advantage. Thus, the saltsor soaps of the amino amide with organic and inorganic acids may be usedto provide added improving characteristics to the agents and to thegasoline compounded therewith. The bicarbonate salts and the salts of asubstituted or unsubstituted acid of phosphorus are particularlydesirable, whereas certain advantages may be gained by the use of saltsof representative organic acids such as benzoic acid, acetic acid, andlauryl acid succinate, etc. When the improving agents are employed inthe form of their salts and particularly as a multi-functional agent,the incorporation of the additives in the gasoline may .vary over awider range such as, for example, from 0.0003 to 1.5 percent by Weight.

In addition to the-subject improving agents in the fuel composition,other conventional fuel additives may be incorporated. An added factorin the reduction of deposits within the air-fuel induction system of theengine may be obtained by the incorporation, in combination with thesubject improving agents, of a nonvolatile oil, such as a light minerallubricating oil or a petroleum spray oil, which functions as a carrierfor the deposits dispersed by the amino amide improving agents.Satisfactory results have been obtained by incorporating a nonvolatileoil in the range of between 0.05 to 0.5 percent by volume and have showneffectiveness in the reduction of deposits in the area of the intakeports of the engine.

The following examples are presented to illustrate the preparation andunique characteristics of representative improving agents of'theinvention.

Example I 100 grams (0.96 mole) of aminoethylethanolamine, 100 grams(0.34 mole) of methyl oleate, and 75 milliliters of benzene were chargedto a reaction flask fitted with a 12-inch fractionating column packedwith glass helices. The reaction temperature was held at 110 to 120 C.while methanol Was removed through the column as a benzene azeotropedistilling at 59 C. The reaction was continued until methanol formationwas complete, which required about 10 hours. A small amount of water wasformed in the reaction and removedas the benzene azeotrope indicatingcyclization of the product.

The reaction product was dissolved in 3 volumes of equal parts ofbenzene and mixed hexanes." The solution Was washed four times with 10percent aqueous sodium chloride solution to remove excess diamine. Thesolvents were removed on the steam plate and aasolid waxy productresulted on cooling.

Titration of a product sample with hydrochloric acid using a Beckrnanglass electrode pH meterindicated a mid pH of 7.7. The pH curveindicated the presence;,of about 10 percent of a stronger base whichpresumably was the cyclization product or imidazolinederivative.

to approximately 7 percent of the isomeric amino tertiaryamide with theresidual amide consisting of the linear amino amide. This product willbe designated in the subsequent tests as mixed amino amide A.

Example 11 This crude amino amide product was purified by tworecrystallizations from mixed hexanes and a final crystallization fromacetone. The white, micro-crystalline product had a melting point of 68to 76 C. The following analyses were obtained:

Calculated Found for the Linear Amide,

Cza n zOl Percent carbon... 71. 38,71. 64 71.68 Percent hydrogen 12. 39,12. 56 12. 03 Percent nitrogen 7. 76, 7. 84 7. 60 Equivalent weight 368369 Tertiary amine content 0. 0 0. 0

This pure linear amino amide will be designated in the subsequent testsas linear amino amide A.

Example III For comparative purposes, the aminoethylethanolamine oleatewas prepared by mixing molecular amounts of the diamine (37 grams) andoleic acid grams). The salt was a sticky solid, and a 60percent-solution in toluene was prepared to facilitate handling.

Example IV Concen- Percent tration, 001 percent;

Mixed amino amide A bicarbonate 26. 8 1. 58, 1. 49 Linear amino amidebicarbonate 28. 6 1. 80, 1. 79

Example V As an example of the variation in the ratio of linear aminoamide to tertiary amino amide in a mixed amino amide product,l-(hydroxyethyl)-2-heptadecenyl-2-imidazoline was hydrolyzed at roomtemperature to obtain a mixed amino amide product containing about 53percent by weight of the corresponding amino tertiary amide, theremainder being the linear isomer. This product is identified insubsequent tests as mixed amino amide B.

Example VI Anadditional improving agent of the invention was the amideproduct obtained by hydrolyzing 1 (hydro xy--ethyl)-2-heptadecyl-2-imidazoline to form a mixture of the isomericamino amides which are identified in the subsequent tests as mixed aminoamide S.

Example VII A laboratory test was deve oped to correlate the formationof carburetor deposits with field experience. In this test, a glassthrottle body is inserted between the float section and the cast ironthrottle body of a conventional carburetor. This glass throttle body isa section of glass tubing A-inch thick, approximately 1% inches insidediameter, and about 2 inches long. About A-inch down from the upperedge, holes are drilled diametrically to receive a conventional metalthrottle plate and shaft. The carburetor and engine employed in the testare those of a 1952 Plymouth.

The engine is started with the throttle plate in the cast iron bodycontrolling the speed, and the throttle plate in the glass body wideopen. When the engine is warmed up so that no danger of backfiringexists, the throttle in the glass body is made to assume the throttlingfunction, and the plate in the iron body is opened wide. Two small tubescarry the idle mixture from the float section to appropriate passagewaysin the cast iron throttle body.

The engine is operated a total of two hours on the test gasoline atabout 500 R. P. M. idle, with five fullthrottle, no-load accelerations,up to a speed of about 3000 R. P. M. every minutes during the testperiod. During each run, all of the engine blowby is piped to theengines air cleaner atop the carburetor. At the end of the test run, theengine is shut down and the glass throttle body removed and rated inaccordance with the degree of deposits on a scale ranging from 1 to 7. Arating of 1 indicates a complete lack of deposits with the throttle bodyclean, and a rating of 7 indicates substantially complete coverage withblack, opaque deposits. This test procedure and the rating of compoundedgasolines obtained thereby have found excellent correlation with actualtest operations in the field.

In accordance with the foregoing test procedure, the followingrepresentative data were obtained:

Fuel Deposit Rating 1 Base fuel (6.0) Base fuel 30 p. p. in. linearamino amide A Base fuel 30 p. p. in. mixed amino amide A Base fuel 30 p.p m. mixed amino amide B 3: 3 Base fuel 30 p. p. m. mixed amino amide Abicarbonate 4. 3 Base fuel 30 p. p In. linear amino amide A bicarbonate4. 3 Base fuel 30 p. p m. mixed amino amide S.. 3.3 Base fuel 30 p. p.m. mixed amino amide S bicarbonate--. 3.0 Base fuel 30 p. p. m.aminoethylethanolamine oleate 6.4

1 A11 deposit ratings corrected to a base fuel rating of 6.0.

The base fuel employed was a commercial leaded regular gasoline which isrepresentative of nationally-available commercial gasolines. As waspreviously mentioned, the hydrocarbon composition of the base fuel has anegligible effect upon the formation of carburetor deposits except as itinfluences the composition of the blowby, and the test results givenabove on the base fuel will be approximately the same, irrespective ofthe stability, gum content, or other characteristics of the hydrocarboncomponents of the fuel.

In addition to the foregoing test data, a gasoline compositioncompounded in accordance with the present invention was field tested inrepresentative fleet service and private automobile operation over anextended period of time with periodic inspection of the air-fuelinduction systems of the engines and in particular the carburetors. Inall instances, the test fuel not only inhibited the formation ofcarburetor deposits, but also was effective in removing existingdeposits Within the carburetor and the intake manifold, and permittedcontinuous satisfactory operation extending beyond periods where,normally, carburetor overhauling was to be expected.

Obviously, many modifications and variations of the out departing fromthe spirit and scope thereof, and therefore only such limitations shouldbe imposed as are indicated in the appended claims.

We claim:

1. A gasoline composition capable of reducing deposits normally formedin the induction system of a sparkignition engine which comprises amajor proportion of a hydrocarbon base fuel boiling within the gasolineboiling range having incorporated therein a small amount, sufficient toreduce said deposits, of an oil-soluble N- aliphatic-substituted aminoalkylene amide of a higher fatty acid containing a terminal hydroxylgroup in the aliphatic substituent, said alkylene and said aliphaticradicals containing from 2 to 4 carbon atoms.

2. An improved gasoline composition which comprises a major proportionof a hydrocarbon base fuel boiling within the gasoline boiling rangehaving incorporated therein about 0.0003 to 1.5 percent by weight of anoilsoluble N-aliphatic-substituted amino alkylene amide of a higherfatty acid containing a terminal hydroxyl group in the aliphaticsubstituent, said alkylene and said allphatic radicals containing from 2to 4 carbon atoms.

3. A gasoline composition capable of reducing deposits normally formedin the induction system of a sparkignition engine which comprises amajor proportion of a hydrocarbon base fuel boiling within the gasolineboiling range having incorporated therein a small amount, sufficient toreduce said deposits, of an oil-soluble aliphatic-substituted aminoalkylene amide of the following formula:

wherein R is an acyclic hydrocarbon radical containing 11 to 17 carbonatoms, A is an alkylene radical containing from 2 to 4 carbon atoms and,in the two occurrences of R, one is hydrogen and the other is C -Caliphatic radical containing a terminal hydroxyl group.

4. An improved gasoline composition which comprises a major proportionof a hydrocarbon base fuel boiling within the gasoline boiling rangehaving incorporated therein about 0.0003 to 1.5 percent by weight of anoilsoluble aliphatic-substituted amino alkylene: amide of the followingformula:

wherein R is an acyclic hydrocarbon radical containing 11 to 17 carbonatoms, A is an alkylene radical containing from 2 to 4 carbon atoms and,in the two occurrences of R, one is hydrogen and the other is C -Caliphatic radical containing a terminal hydroxyl group.

5. An improved gasoline composition which comprises a major proportionof a hydrocarbon base fuel boiling within the gasoline boiling rangehaving incorporated therein about 0.0003 to 1.5 percent by weight of amixture R is C -C aliphatic radical containing a terminal bydroxylgroup.

6.,A gasoline composition capable of reducing deposits normally formedin the induction system of -a sparkignition engine, which comprises amajor proportion of a hydrocarbon base fuel boiling within the gasolineboiling range and containing a small amount, sufiicient to reduce saiddeposits, of bicarbonate salts of the aliphaticsubstituted aminoalkylene amides of claim 3.

3 7. Agasoline composition containing as an improving agent bicarbonatesalts of the amides of claim 5.

v 8. The gasolinecomposition of claim 5 containing, in addition, 0.05 to0.5 percentby volume of a nonvolatile oil.

9. An additive concentrate capable of incorporation into a gasoline,which comprises a hydrocarbon solvent boiling substantially within thegasoline boiling range, having dissolved therein an amount from about 10to (LB about 70% by weight of an oil-soluble acyclic amino alkyleneamide of the formula R-PJ-N-A-NHR' wherein R is an acyclic Cu-Chydrocarbon radical, A is a C -C alkylene radical, and in the twooccurrences of R oneis hydrogen and the other is a C -C aliphaticradical containing a terminal hydroxyl group.

References Cited in the file of this patent UNITED STATES PATENTS2,553,183 Caron et al May 15, 1951 2,622,018 White et al Dec. 16, 19522,638,450 White et al. May 12, 1953

1. A GASOLINE COMPOSITION CAPABLE OF REDUCING DEPOSITS NORMALLY FORMEDIN THE INDUCTION SYSTEM OF A SPARKIDNITION ENGINE WHICH COMPRISES AMAJOR PROPORTION OF A HYDROCARBON BASE FUEL BOILING WITHIN THE GASOLINEBOILING RANGE HAVING INCORPORATED THERIN A SMALL AMOUNT SUFFICIENT TOREDUCE SAID DEPOSITS, OF AN OIL-SOLUBLE NALIPHATIC-SUBSTITUTED, AMINOALKYLENE AMIDE OF A HIGHER FATTY ACID CONTAINING A TERMINAL HYDROXYLGROUP IN THE ALIPHATIC SUBSTITUENT, SAID ALKYLENE AND SAID ALIPHATICRADICALS CONTAINING FROM 2 TO CARBON ATOMS.